package com.example.util;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.stereotype.Component;

import java.time.LocalDateTime;
import java.time.ZoneOffset;
import java.time.format.DateTimeFormatter;

@Component
public class RedisIdWorker {


    private static final long BEGIN_TIMESTAMP = 1704067200;
    private static final int COUNT_BITS = 10;   //序列号的位数

    @Autowired
    private StringRedisTemplate stringRedisTemplate;

    public long nextId(String keyPrefix) {

        //1.生成时间戳
        LocalDateTime now = LocalDateTime.now();
        long nowSecond = now.toEpochSecond(ZoneOffset.UTC);
        long timestamp = nowSecond - BEGIN_TIMESTAMP;
        //2.生成序列号
        //2.获取当前日期 精确到天
        String date = now.format(DateTimeFormatter.ofPattern("yyyy:MM:dd"));
        //2.2自动增值
        long count = stringRedisTemplate.opsForValue().increment("icr:" + keyPrefix + ":" + "2" + date);

        //拼接返回
        return timestamp << COUNT_BITS | count;
    }


}
